The present invention relates to the field of mining machines, and particularly to a roll sizer for breaking apart and crushing mined material.
Conventional mining roll sizers include a pair of parallel counter-rotating roll assemblies positioned within a crushing chamber. The shafts include a series of picks arranged along the surface. As the roll assemblies rotate, the picks engage material that is fed into the crushing chamber, breaking the material apart until it is small enough to pass around the rolls. During normal operation, it is possible for the chamber to receive a tramp material, which is a very hard, dense material. The picks are unable to break apart the tramp material and pass it through the crushing chamber, causing the rolls to bind and one or more picks to break. This requires the roll sizer to be shut down so that the tramp can be removed and any necessary repairs be made to the roll assemblies.